The present invention refers to an apparatus for freezing or deep-freezing food products, in particular products including at least a basic ingredient in the form of individual unitary pieces, and at least one additional ingredient, such as a condiment or the like, containing a relatively high percentage of water (in excess of 40%).
The Italian patent application no. PN93000043, filed on Jun. 18, 1993 by the same applicant as in the present application, discloses a food product of the above-identified type, as well as a method for the production thereof. The patent application particularly covers the production of pasta-based meals, with a sauce being added thereto for flavoring. The meals are then frozen or deep-frozen so as to provide a final product formed in individual unitary pieces, in which sauce granules are attached to the surface of the individual pieces of pasta. Both pasta and sauce are prepared and cooked separately with traditional methods and are then frozen either simultaneously or in successive steps. At the time of serving, i.e. after defrosting, both the pasta and the flavoring sauce appear to be intimately blended with each other and are immediately ready for consumption.
Apparatuses for freezing or deep-freezing food products have been known for a long time. The main drawbacks associated with such known freezing or deep-freezing apparatuses are due to the manner in which the ingredients are stirred or mixed. The stirring or mixing is done by mechanical means, such as a screw or a flight-type shaft rotating inside a rigid vessel. These mechanisms tend to treat the product in such a rough manner that the integrity of the product is frequently spoiled. Furthermore, ice incrustations inevitably form or build up on the vessel walls. Therefore, such mixing means must be provided with scraping means to remove the ice incrustations from the walls of the vessel.
The patent specification EP-A-0093506 discloses a method and an apparatus of the above-mentioned type. The described solution enables a pre-cooked food to be added to a dry and/or powdered substance so as to obtain a single mass of frozen or deep-frozen product which, after defrosting, is able to maintain the original proportions of the ingredients. Therefore, such a solution is not limited to the production of individual portions. On the other hand, the frozen product, given its solid and dense mass, requires a considerable amount of both time and heat in order to obtain a product which is ready to be served and eaten.
The patent specification EP-A-0188359 discloses another similar method and apparatus of the same kind as described in EP-A-0093506 and, therefore, includes basically the same drawbacks.
The patent specification LU 81065 discloses a method of freezing food products made up by vegetables, rice or pasta, in which additional ingredients, such as potato flakes or powdered herbs, are not allowed to contain more than 40% water. As a result, even this method has definite limitations concerning the products which can be obtained on the basis of the raw materials used.
The patent specification FR 2463585 describes a method for freezing liquid food products, in which liquids are frozen into blocks and are then broken into pieces of various shapes and forms, such as granules, spheres, crystals and the like.
Finally, U.S. Pat. No. 3,607,313 describes a method of quick-freezing food products on which a flavoring sauce is sprayed. Single pieces of product, such as green peas, which are entirely coated with sauce and frozen in a mixing drum, are obtained by the method.
As a result, from the current state of the art solutions, such as the afore discussed ones, are emerging which appear to have clear limitations with regard to the type of products that can be processed therewith and/or the complexity of the devices. Also, the prior art devices are not capable of handling the products with the care necessary to obtain frozen food products in single pieces, on the surface of which the additional ingredients, also frozen, may be able to adhere substantially in the form of granules.